摘要
为探究超细粉体惰化剂对铝合金抛丸伴生粉尘爆炸特性的影响规律,利用标准化Hartmann试验装置及自行搭建的试验平台,对不同惰化比(ε)条件下高纯度铝粉尘和铝合金抛丸废弃物粉尘爆炸传播特性进行试验研究。试验结果显示:不同类型的铝粉尘在不同惰化比条件下的爆炸敏感度、爆炸传播强度以及爆炸火焰传播形态演化等方面特性存在较大差异。由于高纯度铝粉尘燃烧反应活性高,最小点火能量和爆炸下限质量浓度分别是铝合金抛丸废弃物粉尘的6%和53.3%,其爆炸火焰传播速度峰值是铝合金抛丸废弃物粉尘的2.1倍。因此,在工程实践中不宜将高纯度铝粉尘相关爆炸参数作为铝合金抛丸作业现场燃烧爆炸风险评估依据。同时,当惰化比提高到30%时,铝合金抛丸废弃物粉尘的点火敏感性大幅降低,爆炸无法形成有效火焰进而传播,且在爆炸发生后很短时间内便会发生自行熄灭,即使在强点火条件下,也未发生火焰持续传播现象。因此,在铝合金抛丸生产现场采用添加一定量超细Al(OH)_(3)粉体以作为抑爆措施的惰化剂具有一定的可行性。
Investigation of explosion sensitivity deactivation and flame propagation mitigation for aluminum alloy shot-blasting waste was carried out by the addition of ultrafine Al(OH)_(3) solid inertants.Meanwhile,high-purity aluminum powders with a similar mean diameter were also used as a comparative study.The explosion propagation characteristics of high-purity aluminum dust and aluminum alloy shot blasting waste dust under different inerting ratios(ε)were tested and studied by using a standardized Hartmann test device and developed experimental platform.Results show that the minimum ignition energy of highpurity aluminum powder is between 4045 mJ,and the minimum ignition energy of aluminum alloy shot-blasting waste is between 700750 mJ,which is one order of magnitude higher than that of high-purity aluminum powders.The lower explosion limit concentration of aluminum alloy shot-blasting waste is 150 g/m 3,which is 53.33%of that of high-purity aluminum powders.By analysis of the SEM image,the main reason is that spherical particles of high-purity aluminum dust have a folded surface and good dispersion.Compared to the smooth fiber surface of the aluminum alloy shot blasting waste,the former is easier to contact with air and the contact area is larger.Therefore,in engineering practice,it is not appropriate to use high-purity aluminum dust-related explosion parameters as the basis for the risk assessment of combustion and explosion in aluminum alloy shot-blasting operation sites.In addition,with the decrease in dust concentration,the combustion intensity of high-purity aluminum dust and aluminum alloy shot blasting waste dust also decreases,and the flame propagation appears discontinuous phenomenon.The peak flame propagation velocity of shot-blasting waste is 6.235 m/s at a concentration of 300 g/m 3,which is 48.12%of that of high-purity aluminum powders.As the increase of inerting ratio,the propagation velocity of the explosion flame is slowed down.When the inerting ratio reaches 30%,the minimum ignition energy of aluminum alloy shot-blasting waste is increased to 1.3 J,self-sustained flame propagation cannot be formed,the results show that the ultrafine Al(OH)_(3) powder has a significant inerting effect,and the realistic possibility.
作者
吕辰
王信群
徐海顺
崔新荣
焦勇
夏新兴
LYU Chen;WANG Xinqun;XU Haishun;CUI Xinrong;JIAO Yong;XIA Xinxing(College of Quality and Safety Engineering,China Jiliang University,Hangzhou 310018,China;Key Laboratory of Safety and High-efficiency Coal Mining,the Ministry of Education(Anhui University of Science and Technology),Huainan 232001,Anhui,China;Lüdun Certified Safety Engineers Firm,Jiaxing 314599,Zhejiang,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2023年第11期3950-3959,共10页
Journal of Safety and Environment
基金
浙江省自然科学基金项目(LQ20E040005,LQ20E040006)
国家重点实验室开放基金项目(JYBSYS2019102)。
关键词
安全工程
铝合金抛丸粉尘
粉尘爆炸
爆炸防控
safety engineering
aluminum alloy shot-blasting dust
dust explosion
explosion mitigation
